A robot cleaner includes a cleaner main body that autonomously travels, a suction nozzle mounted to be able to move up and down or swing with respect to the cleaner main body, and a supporter to support the suction nozzle to be able to move up and down or swing. According to this configuration, the robot cleaner can easily respond to a change in a height of a floor to improve travel performance and implement an action that can help in climbing obstacles. In addition, even when a height difference of the floor is large, cleaning performance can be improved by maintaining a contact stress and increasing a suction pressure of the suction nozzle.